RCMS460

Description:

The RCMS system consists of one or more RCMS460-D/-L or RCMS490-D/-L residual current monitors, which are able to detect and evaluate fault, residual and operating currents in earthed power supplies via the related measuring current transformers. The maximum voltage of the system to be monitored depends on the nominal insulation voltage of the measuring current transformer used in the case of busbar systems, resp. depend on the cables or conductors that are routed through.
Closed W…AB series measuring current transformers are required to measure AC/DC sensitive residual currents (according to IEC/TR 60755: Type B). Six W…AB series measuring current transformers require one AN420 or AN110 power supply unit. W (closed), WR (rectangular), WS (split-core) and WF… (flexible) series measuring current transformers are used for alternating and pulsating currents (according to IEC/TR 60755: Type A).

Any combination of the various measuring current transformer series can be connected to the monitor measuring channels. Each RCMS460-D/-L and RCMS490-D/-L has 12 measuring channels. Up to 90 residual current monitors can be connected via a BMS bus (RS-485 interface with BMS protocol), thereby up to 1080 measuring channels (sub-circuits) can be monitored.

If this product is to be used for personnel, fire or plant protection, the frequency response can be set accordingly. The measured currents can be analysed for harmonics.

Application:

Measuring and evaluating residual, fault and rated currents of loads and installations in the frequency range of 0…2000 Hz (W…AB series measuring current transformers), 42…2000 Hz (W, WR, WS WF series measuring current transformers).

Monitoring of currents regarded as fire hazards in flammable atmospheres

Personnel and fire protection due to rapid disconnection

Monitoring of digital inputs

Function:

The currents are detected and evaluated as true r.m.s. values in the frequency range of 0 (42)…2000 Hz. All channels are scanned simultaneously so that the maximum scanning time for all channels is 180 ms if 1x the response value is exceeded and 30 ms if 5x the
response value is exceeded.
The current values of all channels are indicated on the LC display in bar graph format. If one of both values falls below or exceeds the set response value, the response delay ton begins. Once the response delay has expired, the common alarm relays “K1/K2” switch and the alarm LEDs 1/2 light up.
Two response values/common alarm relays, which can be set separately, allow a distinction to be made between prewarning and alarm. The faulty channel(s) and the associated measured value are indicated on the LC display. If the current exceeds or falls below the release value (response value plus hysteresis), the delay on release toff begins. Once the delay has expired, the common alarm relays return to their initial position.
If the fault memory is enabled, the common alarm relays remain in the alarm state until the reset button is pressed or a reset command is sent via the BMS bus. The device function can be tested using the test button. Parameters are assigned to the device via the LCD and the control buttons on the front of one of the connected RCMS…-D devices or via connected panels and protocol converters (e.g. COM460IP). The preset function allows the response values to be set for all channels considering the currently measured value for each channel.

Features:

Optional AC, pulsed DC or AC/DC sensitive measurement by selecting the respective measuring current transformer for each channel

True r.m.s. value measurement

12 measuring channels per device for residual current measurement or digital input

Up to 90 RCMS… monitors, up to1080 measuring channels in the system

Fast parallel scanning for all channels

Preset function

Adjustable time delays

The frequency response characteristics can be set for the protection of persons, fire and plant protection

History memory with date and time stamp for 300 data records

Data logger for 300 data records/channel

Analysis of the harmonics, DC, THD

Two alarm relays with one changeover contact each

Device version RCMS490 with one alarm contact per channel

N/O or N/C operation and fault memory selectable

Connection external test/reset button

Backlit graphical display (7-segment display) and alarm LEDs

Data exchange via BMS bus

Password protection for device setting

Continuous CT connection monitoring

RoHS compliant

Digital input:Each individual channel can be used for one of the following monitoring functions:
as digital input using a potential-free contact 1/0 or for current or residual current monitoring in combination with measuring current transformers.